1. Technical Field
The present invention relates to an activity monitor, a method of calculating a target activity amount, and a storage medium in which a program for the activity monitor is stored.
2. Related Art
Total energy expenditure of a human can be broadly classified into basal metabolism and energy expenditure through physical activities. In addition, it is known that meal-induced thermogenesis, which is an increase in body temperature that takes place after a meal, also consumes energy. When the total energy expenditure exceeds energy intake, primarily fat is burnt and body weight is reduced. Thus far, various activity monitors that measure the total energy expenditure have been developed.
For example, JP-A No. 2005-58614 discloses an activity monitor for women that calculates the total energy expenditure taking into account variations in physiological condition of women. The activity monitor estimates the physiological condition of a user on the basis of information indicating the number of elapsed days from the first day of a menstrual period, to thereby accurately calculate the user's basal metabolism and energy expenditure by exercise. The activity monitor first calculates a target fat-burning energy per day by dividing a target amount of fat loss by a target period of the diet, and outputs a target number of steps converted from the target fat-burning energy. In this calculation, the activity monitor takes into account the fact that the basal metabolism and exercise efficiency of women vary between a luteal phase and a follicular phase in a menstrual cycle. More specifically, the activity monitor decides whether the female user is in the luteal phase or the follicular phase, and applies a correction coefficient statistically determined in advance to thereby calculate the target number of steps corresponding to the target fat-burning energy per day, with respect to each phase of the menstrual cycle.
[Patent Document 1] Japanese Laid-open patent publication No. 2005-58614
To calculate the target number of steps corresponding to the target fat-burning energy per day during the luteal phase and the follicular phase with the activity monitor according to Patent Document 1, a luteal phase correction coefficient and a follicular phase correction coefficient, respectively determined statistically in advance, are employed. Since these correction coefficients are statistic values obtained on the basis of physical features, the same correction coefficients are applied to a plurality of users having common basic physical data such as age, sex, and weight. Accordingly, the same target number of steps is proposed in common to different users having the same basic physical data, provided that the users are aiming at the same diet goal (for example, losing 3 kgs. in three months).
However, although the basic physical data of the users is the same, some users wish to reduce fat primarily by limiting energy intake (amount of meal), so-called an eat less/move less type, while some users wish to actively perform exercises without limiting the energy intake, an eat more/move more type. This is the case with both male and female users. In the case of women, some users actively perform exercises even during the menstrual period, while some choose to refrain from exercising during the menstrual period. Thus, specific activity patterns for the diet largely vary depending on the users. The activity monitor according to Patent Document 1, therefore, still has a room for improvement from the viewpoint of offering meticulous options of the target number of steps so as to fit the activity patterns that are different by users irrespective of sex.